CHEMISTRY

OBJECTIVES OF THE COURSE

The students will be prepared to a correct and deep understanding of the fundamental mechanisms which govern the chemical transformation of matter in the main fields of interest for the Environmental and Land Management Engineering.

COURSE CONTENTS SUMMARY

Introduction. Elements and compounds. Chemical and physical phenomena. Systems. Main physical units. The SI system. Mixtures and compounds. Determination of the atomic masses.

The structure of the matter. Fundamental particles of the atom. Atomic number. Mass number. Isotopes. Atomic mass. Mass spectrometry. The concept of mole. The defect of mass. Exercises.

Stoicheiometry. Chemical formulas. Molar mass. Chemical equations and their balance. Calculations of the masses or reagents and products. Limiting reagent. Calculations of the % from the formula and viceversa.

The origin of the quantum theory. Electromagnetic radiations and atomic spectra. The hypothesis of Planck. The Hydrogen atom according Bohr. Electronic transitions in the hydrogen atom and frequencies of its spectrum. The wave-particle dualism of the electron. The Heisenber principle. The Schroedinger equation. Quantum numbers. Orbitals and their limiting surfaces. The spin of the eclectron.

The atoms in the periodic system. The Aufbau method. The Pauli’s principle and the Hund’s rule. Electronic configurations. Periods, groups, transition series. Periodic properties and types of elements.

Chemical bond. The ionic bond. The covalent bond according to the V.B. theory. The Lewis formulas. The octet rule and its limits. The molecular geometry according to the VSEPR theory: exercises. The resonance. Electronegativity as a periodic property. The polar covalent bond. The dipole moment and the % of ionic character. Exaples of polar molecules. The V.B. method. Ionic-covalent resonance. The electronegativity according to Mulliken and to Pauling.. Hybrid orbitals sp, sp2, sp3. Benzene and its resonance formulas. The hydrogen bond. Intermolecular forces of van der Waals. The metal bond. Conductors and insulators.

Chemical nomenclature and reactivity. Oxydation number (definition and rules for). The balance of a redox reaction. Main oxidant and reducing agents. The nomenclature of the binary compounds. The nomenclature of ions. Ionic hydrides. Covalent hydrides. Hydracids. Ionic oxides. Covalent oxydes. Hydroxides. Oxoacids. Salts.

Thermodynamics. Introduction. The state of a system. Variables and state functions. Reversible and irreversible transformations. The First Law. Henthalpy. Molar heats Cv e Cp. Entropy. The Second Law. Entropy and statistic. The entropy change in an isolated system. The Third Law. Thermochemistry: the Lavoisier-Laplace’s law. The Hess’s law. Examples. Standard hentalpies. Standard entropies. Bond energies and heat of a reaction. Helmoltz’s and Gibbs’s free energies. Exercises.

The solid state. General properties. The crystal lattice and the unit cell. Crystallographic classes. Crystal systems and Bravais lattices. Calculation of the unit cell volume from the density and viceversa. Covalent crystals. Molecular crystals. Polimorphism.

The solutions. Definitions. Electrolitic and non-electrolitic solutions. Hentalpy of an electrolitic solution: the Born-Haber’s Cycle. The calculation of the concentrations of a solution. Ideal solutions. Vapor pressure of a solution. The Raoult’s law. The colligative properties. The van’t Hoff’s coefficient. Exercises.